Have you had your first dose of the AstraZeneca vaccine yet? We break down the common side effects and how much immunity you will develop. 

Malaysia has embarked on a voluntary vaccination of the Oxford-AstraZeneca-developed Covid-19 vaccine. Over a million Malaysians and expats have received or are in line to receive their first doses. 

Hero & featured image credit: Unsplash/CDC

It is normal to experience short-term side effects that persist for 48 hours, though the severity depends on individuals. While side effects are signs that the vaccine is teaching your body’s immune system how to combat the virus and protect yourself from the disease, not everyone will experience side effects. If you don’t experience these side effects, it doesn’t mean that the vaccine isn’t working as intended. People of younger age tend to experience side effects due to the response of a more robust immune system. 

Common side effects include soreness in the arm where the injection takes place, headache, chills, fever and debility. The UK National Health Service (NHS) suggests taking paracetamol to alleviate the symptoms. An uncommon side effect is swollen glands in the armpit or neck which may last around 10 days. 

For those who have recovered from Covid-19, you are more likely to experience side effects after being administered the vaccine than someone who hasn’t been infected by Covid-19.  

When do you actually develop some sort of immunity? 

Study shows that a single dose of the AstraZeneca vaccine is 76% effective at protecting against Covid-19 with symptoms for at least 90 days. It takes about three weeks for the first dose to work. Research also shows that the efficacy of the vaccine is higher when two doses are further apart – 81% for the 12-week interval compared to 55% for the six-week interval.  

For the B.1.617.2 and B.1.1.7 variants originally discovered in India and the UK respectively, a single dose is found to be 33% and 50% effective respectively. Efficacies rise to 60% and 66% respectively after two doses are administered. 

Against the B.1.351 strain discovered first in South Africa, two doses of this vaccine demonstrated not-so-optimistic efficacy, hovering around 10%. Nonetheless, there were no cases of hospitalisation due to severe Covid-19 infection during the study. While this strain has seeped into the community, it is not the dominant strain in circulation. 

If you have had an infection, you are still recommended to be vaccinated as the naturally developed immunity might not last and consequently result in a second infection. It may not also protect you from the propagating variants. 


Vaccination offers not only immunity but also peace of mind (Image credit: Trisara)
What about the risk? 

It is reported that the AstraZeneca vaccine might present an extremely small risk of developing life-threatening conditions. The risk of developing thrombosis, however, is negligible compared to the risks posed by contraceptive pills and smoking – and especially Covid-19 infection itself. The benefits of the vaccine far outweigh the risks of contracting the virus.  

Symptoms of rare blood clots might surface four days after vaccination. What we know so far is that cases of thrombosis primarily involve women under 55. 

The NHS recommends you seek immediate help if you experience a severe headache that is not relieved with painkillers or is getting worse; a headache that feels worse when you lie down or bend over; a headache that is unusual for you and occurs with blurred vision, feeling or being sick, problems speaking, weakness, drowsiness or seizures; a rash that looks like small bruises or bleeding under the skin; or shortness of breath, chest pain, leg swelling or persistent abdominal pain. 

How did we get here?  

The first round of the optional immunisation plan was announced on April 28 after a decision was made based on lingering concerns and hesitancy towards the vaccine. The first batch of 268,800 doses courtesy of COVAX was pulled from the main pool of vaccines for the current national immunisation plan. Re-channelled towards Malaysians and expats above 18 years old residing in the Klang Valley, the availability was snapped up in over three hours after the programme was open on a first-come-first-serve basis on May 2. The vaccine administration started on May 5. 

Upon a warm reception by the public but also frustrations that senior citizens were overlooked, the second round of the optional AstraZeneca vaccination programme was announced on May 21. The priority was given to adults aged 60 and above across the Klang Valley, Johor, Penang and Sarawak between May 23 and 26, while the remaining vacancies were filled by Malaysians and expats above 18 years old residing in the aforementioned states in just over an hour on May 26. A total of 1.24 million doses were on offer in the second round. 

Following the second round, it is reported that the opt-in programme will cease and AstraZeneca will be reincorporated into the national immunisation plan. 

Justin Ng
Digital Content Director, Kuala Lumpur
Often think of myself as a journalist and so I delve deeper into a range of topics. Talk to me about current affairs, watches, travel, drinks, new experiences and more importantly, the business, economics and dynamics behind it.